Healthy Men and WomenNCT03995602
The Effects of Dragon Fruit Consumption on Vascular Function.
A study testing Dragon fruit juice drink in people with Healthy Men and Women, run by King's College London at 1 site in United Kingdom.
Trial summary
Native to South America and South East Asia, the dragon fruit (pitaya) has become increasingly popular world-wide due to their vivid hue and bizarre structure. More importantly, their high levels of bioactive phytochemical betalains has sparked considerable scientific interest. Read more about this study
- Who is it for?
- Ages 18 to 40 yearsHealthy volunteers can take part
- Conditions the study is for
- Healthy Men and Women
- What is being tested?
- Dragon fruit juice drink
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 20 participants
- Where
- 1 siteUnited Kingdom
- Study dates
- 18 Jun 2019to 22 Jan 2020
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 40 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Healthy men and women aged 18-40 years old
- Subjects are willing to maintain their normal eating/drinking habits and exercise habits to avoid changes in body.
- weight over the duration of the study.
- Are able to understand the nature of the study.
- Able to give signed written informed consent.
- Signed informed consent form.
Who cannot join
- Medical history of cardiovascular disease including coronary artery disease, cerebrovascular disease and peripheral artery disease.
- Hypertensive, as defined as SBP superior or equal to 140 mmHg.
- Obese participants, defined as BMI superior or equal to 30.
- Medical history of diabetes mellitus, metabolic syndrome, terminal renal failure or malignancies.
- Abnormal heart rhythm (lower or higher than 60-100 bpm).
- Allergies to dragon fruit, cactus pear or other significant food allergy.
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- Subjects under medication that can affect the cardiovascular system or on vitamin/dietary supplements.
- Subjects who have lost more than 10% of their weight in the past 6 months or are currently in a diet
- Subjects who reported participant in another study within one month before the study start.
- Subjects who smokes.
- Pregnant women or planning to become pregnant in the next 6 months.
- Any reason or condition that in the judgment of the clinical investigator(s) may put the subject at unacceptable risk or that may preclude the subject from understanding or complying with the study's requirements.
Trial locations and contacts
1 site in 1 country.
About this study
Official title: A Randomised, Placebo-controlled, Crossover Study of the Effects of Dragon Fruit Effects of Dragon Fruit (Pitaya) Consumption on Vascular Function in Healthy Males and Females
Native to South America and South East Asia, the dragon fruit (pitaya) has become increasingly popular world-wide due to their vivid hue and bizarre structure. More importantly, their high levels of bioactive phytochemical betalains has sparked considerable scientific interest. Recent findings from in vitro and in vivo animal studies tentatively suggest that betalains may have ameliorative effects on vascular function. This will be a first randomised controlled trial aimed to explore the impact of dragon fruit consumption on blood pressure and other vascular parameters in healthy individuals. The study will feature a randomised, double-blinded, placebo-controlled and crossover design with flow-mediated dilatation (FMD) as primary outcome along with blood pressure and arterial stiffness as secondary outcomes. Cardiovascular biomarkers as well as relevant metabolites will also be determined from blood and urine samples collected from participants.
- Conditions
- Healthy Men and Women
- Being tested
- Dragon fruit juice drink, Placebo
- Keywords
- vascular function, endothelial function, betalains, dragon fruit, pitaya
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Dragon fruit juice drinkDietary supplement
Dragon fruit drink containing 24 g of freeze-dried dragon fruit powder dissolved in low nitrate water.
PlaceboDietary supplement
Drink with macro- and micro-nutrient matched against the intervention drink.
| Study group | Role | What they receive |
|---|---|---|
| Dragon fruit first then placebo | Experimental | 2 weeks of dragon fruit juice intake or placebo with crossover to the other Receives: Dietary Supplement: Dragon fruit juice drink; Dietary Supplement: Placebo |
| Placebo first then dragon fruit | Experimental | 2 weeks of dragon fruit juice intake or placebo with crossover to the other Receives: Dietary Supplement: Dragon fruit juice drink; Dietary Supplement: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Changes in flow mediated dilation (FMD) of the brachial artery
Determine changes in flow mediated dilation (FMD) of the brachial artery after 2 weeks consumption of 24 g freeze-dried dragon fruit.
Measured: Baseline & 2 weeks
Secondary outcomes (8)
Changes in flow mediated dilation (FMD) of the brachial artery
Determine changes in flow mediated dilation (FMD) of the brachial artery at 2, 3, and 4 hour post consumption of 24 g freeze-dried dragon fruit.
Measured: Baseline & 2, 3 and 4 hour post-consumption
Changes in blood pressure
Determine changes in systolic and diastolic blood pressure at 2, 3, and 4 hour post consumption of 24 g freeze-dried dragon fruit.
Measured: Baseline & 2, 3 and 4 hour post-consumption
Changes in blood pressure
Determine changes in systolic and diastolic blood pressure after 2 weeks post consumption of 24 g freeze-dried dragon fruit.
Measured: Baseline & 2 weeks
Changes in heart rate
Determine changes in heart rate post consumption of 24 g freeze-dried dragon fruit.
Measured: Baseline & 2, 3 and 4 hour and 2 weeks post-consumption
Changes blood flow velocity
Determine changes in blood flow velocity post consumption of 24 g freeze-dried dragon fruit.
Measured: Baseline & 2, 3 and 4 hour and 2 weeks post-consumption
Changes in pulse wave velocity (PWV)
Determine changes in pulse wave velocity post consumption of 24 g freeze-dried dragon fruit.
Measured: Baseline & 3 hour and 2 weeks post-consumption.
Changes augmentation Index (AIx)
Determine changes in augmentation index post consumption of 24 g freeze-dried dragon fruit.
Measured: Baseline & 3 hour and 2 weeks post-consumption.
Number of volunteers with treatment-related adverse events
The number of volunteers with treatment-related adverse events will be assessed by questionnaires and interviews.
Measured: Baseline & 12 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted24 Jun 2019
- Study start18 Jun 2019
- Primary completion22 Jan 2020
- Study completion22 Jan 2020
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Healthy Men and WomenStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Triple blind
- Who is masked
- Participant, Investigator, Outcomes assessor
- Enrolment
- 20 participants (actual)
Sponsor and investigators
- Lead sponsor
- King's College London
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Dr Ana Rodriguez-Mateos, King's College London
- Investigators
- Ana Rodriguez-Mateos, PhD, Principal investigator, King's College London
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03995602
- Sponsor's protocol ID
- DRAGON Study
- Status last verified
- Jun 2021
- First submitted
- 20 Jun 2019
- Last updated
- 7 Jun 2021
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Cheok A, Xu Y, Zhang Z, Caton PW, Rodriguez-Mateos A. Betalain-rich dragon fruit (pitaya) consumption improves vascular function in men and women: a double-blind, randomized controlled crossover trial. Am J Clin Nutr. 2022 May 1;115(5):1418-1431. doi: 10.1093/ajcn/nqab410.
PubMed 35265960
Study at a glance
From the registry record, last updated by the sponsor on 7 Jun 2021. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Randomised, Placebo-controlled, Crossover Study of the Effects of Dragon Fruit Effects of Dragon Fruit (Pitaya) Consumption on Vascular Function in Healthy Males and Females
- ClinicalTrials.gov ID
- NCT03995602
- Acronym / sponsor ID
- DRAGON Study
- Conditions
- Healthy Men and Women
- Keywords
- vascular function, endothelial function, betalains, dragon fruit, pitaya
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 20 participants (actual)
- Lead sponsor
- King's College LondonUniversity, hospital or other
- Study start
- 18 Jun 2019 (actual)
- Primary completion
- 22 Jan 2020 (actual)
- Study completion
- 22 Jan 2020 (actual)
- First posted
- 24 Jun 2019 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Native to South America and South East Asia, the dragon fruit (pitaya) has become increasingly popular world-wide due to their vivid hue and bizarre structure. More importantly, their high levels of bioactive phytochemical betalains has sparked considerable scientific interest. Recent findings from in vitro and in vivo animal studies tentatively suggest that betalains may have ameliorative effects on vascular function. This will be a first randomised controlled trial aimed to explore the impact of dragon fruit consumption on blood pressure and other vascular parameters in healthy individuals. The study will feature a randomised, double-blinded, placebo-controlled and crossover design with flow-mediated dilatation (FMD) as primary outcome along with blood pressure and arterial stiffness as secondary outcomes. Cardiovascular biomarkers as well as relevant metabolites will also be determined from blood and urine samples collected from participants.
Study design
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Triple blind (participant, investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Dragon fruit first then placebo | Experimental | Dietary Supplement: Dragon fruit juice drink, Dietary Supplement: Placebo2 weeks of dragon fruit juice intake or placebo with crossover to the other |
| Placebo first then dragon fruit | Experimental | Dietary Supplement: Dragon fruit juice drink, Dietary Supplement: Placebo2 weeks of dragon fruit juice intake or placebo with crossover to the other |
Who may qualify
- Ages
- 18 to 40 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (6 listed)
- Healthy men and women aged 18-40 years old
- Subjects are willing to maintain their normal eating/drinking habits and exercise habits to avoid changes in body.
- weight over the duration of the study.
- Are able to understand the nature of the study.
- Able to give signed written informed consent.
Key exclusion criteria (12 listed)
- Medical history of cardiovascular disease including coronary artery disease, cerebrovascular disease and peripheral artery disease.
- Hypertensive, as defined as SBP superior or equal to 140 mmHg.
- Obese participants, defined as BMI superior or equal to 30.
- Medical history of diabetes mellitus, metabolic syndrome, terminal renal failure or malignancies.
- Abnormal heart rhythm (lower or higher than 60-100 bpm).
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Dragon fruit juice drinkDragon fruit drink containing 24 g of freeze-dried dragon fruit powder dissolved in low nitrate water. | Dietary supplement | Dragon fruit first then placebo, Placebo first then dragon fruit |
| PlaceboDrink with macro- and micro-nutrient matched against the intervention drink. | Dietary supplement | Dragon fruit first then placebo, Placebo first then dragon fruit |
Primary outcome
Changes in flow mediated dilation (FMD) of the brachial artery
Time frame: Baseline & 2 weeks
Determine changes in flow mediated dilation (FMD) of the brachial artery after 2 weeks consumption of 24 g freeze-dried dragon fruit.
8 secondary outcomes
Changes in flow mediated dilation (FMD) of the brachial artery
Time frame: Baseline & 2, 3 and 4 hour post-consumption
Changes in blood pressure
Time frame: Baseline & 2, 3 and 4 hour post-consumption
Changes in blood pressure
Time frame: Baseline & 2 weeks
Changes in heart rate
Time frame: Baseline & 2, 3 and 4 hour and 2 weeks post-consumption
Changes blood flow velocity
Time frame: Baseline & 2, 3 and 4 hour and 2 weeks post-consumption
Changes in pulse wave velocity (PWV)
Time frame: Baseline & 3 hour and 2 weeks post-consumption.
Changes augmentation Index (AIx)
Time frame: Baseline & 3 hour and 2 weeks post-consumption.
Number of volunteers with treatment-related adverse events
Time frame: Baseline & 12 weeks
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 7 Jun 2021.
- Derived from this study: PubMed 35265960Cheok A, Xu Y, Zhang Z, Caton PW, Rodriguez-Mateos A. Betalain-rich dragon fruit (pitaya) consumption improves vascular function in men and women: a double-blind, randomized controlled crossover trial. Am J Clin Nutr. 2022 May 1;115(5):1418-1431. doi: 10.1093/ajcn/nqab410.
- Individual participant dataSharing planned: No
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Ana Rodriguez-Mateos, PhD principal investigator
King's College London
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Dragon fruit juice drink in people with Healthy Men and Women, run by King's College London at 1 site in United Kingdom.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 12 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 7 Jun 2021. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United Kingdom. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Changes in flow mediated dilation (FMD) of the brachial artery (time frame: Baseline & 2 weeks). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT03995602, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 7 Jun 2021.